CVE-2020-10932 | Date: (C)2020-04-16 (M)2023-12-22 |
An issue was discovered in Arm Mbed TLS before 2.16.6 and 2.7.x before 2.7.15. An attacker that can get precise enough side-channel measurements can recover the long-term ECDSA private key by (1) reconstructing the projective coordinate of the result of scalar multiplication by exploiting side channels in the conversion to affine coordinates; (2) using an attack described by Naccache, Smart, and Stern in 2003 to recover a few bits of the ephemeral scalar from those projective coordinates via several measurements; and (3) using a lattice attack to get from there to the long-term ECDSA private key used for the signatures. Typically an attacker would have sufficient access when attacking an SGX enclave and controlling the untrusted OS.
CVSS Score and Metrics +CVSS Score and Metrics -CVSS V3 Severity: | CVSS V2 Severity: |
CVSS Score : 4.7 | CVSS Score : 1.9 |
Exploit Score: 1.0 | Exploit Score: 3.4 |
Impact Score: 3.6 | Impact Score: 2.9 |
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CVSS V3 Metrics: | CVSS V2 Metrics: |
Attack Vector: LOCAL | Access Vector: LOCAL |
Attack Complexity: HIGH | Access Complexity: MEDIUM |
Privileges Required: LOW | Authentication: NONE |
User Interaction: NONE | Confidentiality: PARTIAL |
Scope: UNCHANGED | Integrity: NONE |
Confidentiality: HIGH | Availability: NONE |
Integrity: NONE | |
Availability: NONE | |
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